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Amyotrophic lateral sclerosis is a disease characterized by progressive paralysis and death. Most ALS-cases are sporadic (sALS) and patient heterogeneity poses challenges for effective therapies. Applying metabolite profiling on 77-sALS patient-derived-fibroblasts and 43-controls, we found ~25% of sALS cases (termed sALS-1) are characterized by transsulfuration pathway upregulation, where methionine-derived-homocysteine is channeled into cysteine for glutathione synthesis. sALS-1 fibroblasts selectively exhibited a growth defect under oxidative conditions, fully-rescued by N-acetylcysteine (NAC). [U13C]-glucose tracing showed transsulfuration pathway activation with accelerated glucose flux into the Krebs cycle. We established a four-metabolite support vector machine model predicting sALS-1 metabotype with 97.5% accuracy. Both sALS-1 metabotype and growth phenotype were validated in an independent cohort of sALS cases. Importantly, plasma metabolite profiling identified a system-wide cysteine metabolism perturbation as a hallmark of sALS-1. Findings reveal that sALS patients can be stratified into distinct metabotypes with differential sensitivity to metabolic stress, providing novel insights for personalized therapy.

Objective: Adherence to combination antiretroviral therapy (ART) among pregnant women is essential to attaining the goal of eliminating mother-to-child HIV transmission. The objective of this study was to determine which factors affect adherence to ART among HIV-positive women enrolled in a large prevention of mother-to-child HIV transmission (PMTCT) trial in rural north-central Nigeria. Methods: The parent study included 372 HIV-positive pregnant women enrolled in a cluster-randomized control trial conducted at 12 health facilities in Nigeria between 2013 and 2015. This secondary analysis included HIV-positive women (and their infants) from the original trial with documented adherence data (n=210, 56.5%). The primary outcome was maternal adherence to ART, determined by self-report and based on the visual analogue scale (VAS) of a validated medication adherence tool. Participants with a VAS score of ? 95% were classified as adherent. We employed multivariate logistic regression to evaluate the predictors of maternal ART adherence in the study sample. Results: Approximately 61.0% of study participants (128/210) were adherent to ART. The majority of adherent participants (62.5%, 80/128) were enrolled in the trial intervention arm. The most common cited response for non-adherence was fear of status disclosure. Adherence to ART was associated with study arm (intervention arm vs. control arm, adjusted Odds Ratio (aOR) [95% CI]: 16.95 [5.30-54.23]), maternal ethnicity (Gwari vs. Other, aOR = 0.13 [0.05-0.38]), and partner HIV status (HIV-positive vs. unknown, aOR = 3.14 [1.22-8.07]). Conclusion and Global Health Implications: Adherence to ART among a cohort of pregnant women enrolled in a PMTCT trial in rural North-Central Nigeria was associated with trial arm, maternal self- reported ethnicity, and partner’s HIV status. Increased understanding of the interplay between these factors will enable the development of more targeted and effective interventions. Key words: • HIV/AIDS • PMTCT • Combination antiretroviral therapy • Adherence • PMCTC • Nigeria Copyright © 2020 Calder et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Retinal vascular diseases have distinct, complex and multifactorial pathogeneses yet share several key pathophysiological aspects including inflammation, vascular permeability and neovascularisation. In non-infectious posterior uveitis (NIU), retinal vasculitis involves vessel leakage leading to retinal enlargement, exudation, and macular oedema. Neovascularisation is not a common feature in NIU, however, detection of the major angiogenic factor—vascular endothelial growth factor A (VEGF-A)—in intraocular fluids in animal models of uveitis may be an indication for a role for this cytokine in a highly inflammatory condition. Suppression of VEGF-A by directly targeting the leukotriene B4 (LTB4) receptor (BLT1) pathway indicates a connection between leukotrienes (LTs), which have prominent roles in initiating and propagating inflammatory responses, and VEGF-A in retinal inflammatory diseases. Further research is needed to understand how LTs interact with intraocular cytokines in retinal inflammatory diseases to guide the development of novel therapeutic approaches targeting both inflammatory mediator pathways.

The transcription factor T-bet directs Th1 cell differentiation, but the molecular mechanisms that underlie this lineage-specific gene regulation are not completely understood. Here, we show that T-bet acts through enhancers to allow the recruitment of Mediator and P-TEFb in the form of the super elongation complex (SEC). Th1 genes are occupied by H3K4me3 and RNA polymerase II in Th2 cells, while T-bet-mediated recruitment of P-TEFb in Th1 cells activates transcriptional elongation. P-TEFb is recruited to both genes and enhancers, where it activates enhancer RNA transcription. P-TEFb inhibition and Mediator and SEC knockdown selectively block activation of T-bet target genes, and P-TEFb inhibition abrogates Th1-associated experimental autoimmune uveitis. T-bet activity is independent of changes in NF-κB RelA and Brd4 binding, with T-bet- and NF-κB-mediated pathways instead converging to allow P-TEFb recruitment. These data provide insight into the mechanism through which lineage-specifying factors promote differentiation of alternative T cell fates.

BackgroundNon-infectious uveitis can cause chronic relapsing and remitting ocular inflammation, which may require high dose systemic immunosuppression to prevent severe sight loss. It has been classically described as an autoimmune disease, mediated by pro-inflammatory Th1 and Th17 T-cell subsets. Studies suggest that natural immunosuppressive CD4+CD25+FoxP3+ T-regulatory cells (Tregs) are involved in resolution of inflammation and may be involved in the maintenance of clinical remission.ObjectiveTo investigate whether there is a peripheral blood immunoregulatory phenotype associated with clinical remission of sight-threatening non-infectious uveitis by comparing peripheral blood levels of Treg, Th1, and Th17, and associated DNA methylation and cytokine levels in patients with active uveitic disease, control subjects and patients (with previously active disease) in clinical remission induced by immunosuppressive drugs.MethodsIsolated peripheral blood mononuclear cells (PBMC) from peripheral blood samples from prospectively recruited subjects were analyzed by flow cytometry for CD3, CD4, FoxP3, TIGIT, T-bet, and related orphan receptor γt. Epigenetic DNA methylation levels of FOXP3 Treg-specific demethylated region (TSDR), FOXP3 promoter, TBX21, RORC2, and TIGIT loci were determined in cryopreserved PBMC using a next-generation sequencing approach. Related cytokines were measured in blood sera. Functional suppressive capacity of Treg was assessed using T-cell proliferation assays.ResultsFifty patients with uveitis (intermediate, posterior, and panuveitis) and 10 control subjects were recruited. The frequency of CD4+CD25+FoxP3+ Treg, TIGIT+ Treg, and T-bet+ Treg and the ratio of Treg to Th1 were significantly higher in remission patients compared with patients with active uveitic disease; and TIGIT+ Tregs were a significant predictor of clinical remission. Treg from patients in clinical remission demonstrated a high level of in vitro suppressive function compared with Treg from control subjects and from patients with untreated active disease. PBMC from patients in clinical remission had significantly lower methylation levels at the FOXP3 TSDR, FOXP3 promoter, and TIGIT loci and higher levels at RORC loci than those with active disease. Clinical remission was also associated with significantly higher serum levels of transforming growth factor β and IL-10, which positively correlated with Treg levels, and lower serum levels of IFNγ, IL-17A, and IL-22 compared with patients with active disease.ConclusionClinical remission of sight-threatening non-infectious uveitis has an immunoregulatory phenotype characterized by upregulation of peripheral Treg, polarized toward T-bet and TIGIT. These findings may assist with individualized therapy of uveitis, by informing whether drug therapy has induced phenotypically stable Treg associated with long-term clinical remission.

HMG-CoA reductase inhibitors (statins) have been demonstrated to be immunomodulatory for human immune-mediated disease and in experimental models. The aim of this study was to compare statin-mediated immunosuppressive effects on human T-cell responses in vitro with those of conventional immunosuppressives (dexamethasone, cyclosporin A (CsA), mycophenolate, and rapamycin). Statins (atorvastatin, lovastatin, and simvastatin) were investigated for their modulatory effects on human PBMC viability, cytokine profiles, and T-cell proliferation. At concentrations that inhibited anti-CD3/28-stimulated T-cell proliferation (), simvastatin significantly decreased intracellular CD4+ T-cell expression of IFN- () to levels similar to those induced by conventional immunosuppressives. Atorvastatin and lovastatin also decreased IFN- expression, although to a lesser degree (). All three statins reduced levels of IL-17 production (). However, in response to anti-CD3/28 stimulation, simvastatin significantly upregulated IL-1 production (). The profile of cytokines produced in response to anti-CD3/28 stimulation was similar when both atorvastatin and dexamethasone were added as compared with dexamethasone alone, suggesting that atorvastatin can synergise with dexamethasone with respect to immunomodulation of cytokines. This data supports the hypothesis of selective statin-mediated immunomodulatory effects on human immune cells.